Ootheca is formed in cockroach by:

Options

A. Phallic Gland
B. Conglobate gland
C. Utricular gland
D. Collaterial gland

Answer

**Step-by-Step Solution:**

1. **Understanding Ootheca Formation**: The ootheca is a protective casing that contains the eggs of the cockroach. It is crucial to know which glands are involved in its formation.

2. **Identifying the Glands**: The question provides four options: phallic gland, conglobate gland, utricular gland, and collateral gland. We need to determine which of these glands is responsible for the secretion of materials that form the ootheca.

3. **Role of Collateral Glands**: The collateral glands are known to open into the vestibule of the female cockroach. They secrete proteins and tanning agents that are essential for the formation of the ootheca.

4. **Secretion of Structural Proteins**: The proteins secreted by the collateral glands contribute to the formation of the outer layer of the ootheca, which is alkaline resistant. Additionally, structural proteins are secreted from the anterior and posterior parts of the cockroach, which are also involved in ootheca formation.

5. **Conclusion**: Based on the information regarding the function of the collateral glands and their role in secreting the necessary materials for the ootheca, we conclude that the correct answer is the collateral glands.

**Final Answer**: Ootheca is formed in cockroach by collateral glands.

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